ByMatthew Daly, Associated PressSeptember 23, 2011

Solyndra CEO Brian Harrison (l.) and Chief Financial Officer Bill Stover are sworn in on Capitol Hill in Washington, Friday, prior to testifying before the House Oversight and Investigations subcommittee. Top executives from a bankrupt California solar energy company are to appear before a congressional hearing investigating their government loan.

Lawmakers from both parties said they were disappointed, but said that silence from the two executives would not stop them from pursuing their investigation into a $528 million loan that Solyndra Inc. received from the Energy Department in 2009.

"It appears we have a great heist of over half a billion dollars and ... maybe even co-conspirators called the U.S. government," Upton said.

Upton faulted the Obama administration for its role in the loan, saying at a minimum the Energy Department did not complete due diligence on the company, which lost hundreds of millions of dollars in the years before the loan was approved.

He called the loan "reckless use of taxpayer dollars on a company that was known to pose serious risks before a single dime went out the door."

Meanwhile, fallout from the Solyndra controversy continued. A solar company slated to get a separate Energy Department loan guarantee said Friday it has been told the guarantee will not be approved in time to meet a federal deadline.

The Energy Department said earlier this month it would provide a partial guarantee for a $344 million loan to San Mateo, Calif.-based SolarCity to install solar panels on 160,000 homes across 124 military bases in 33 states.

But SolarCity said in a letter to Congress Friday that the project now appears to be dead. "In the past 48 hours, DOE has informed us ... they will be unable to finalize the loan guarantee" by Sept. 30, the company said in a letter to Upton and other committee leaders. "The reason provided was the increased documentation requirements that are the result of the current congressional investigation into the Solyndra bankruptcy."

The announcement came after two other solar firms, First Solar and Solar Trust of America, said they would not be able to accept loan guarantees worth about $4 billion for major solar projects in Southern California because they could not meet the Sept. 30 deadline.

SolarCity CEO Lyndon Rive called his company a victim of Solyndra, and urged Congress to extend the Sept. 30 deadline by a few weeks to allow his project and others to move forward. DOE says as many as 10 projects worth more than $6 billion face the Sept. 30 deadline.

"It's a shame to pull the plug on this project just because of the Solyndra bankruptcy," Rive said.

An Energy Department official confirmed that the SolarCity project would not close by Sept. 30, but would not say the reason.

Spokesman Damien LaVera said in an email that the department has consistently said it will not close any deal until rigorous technical, legal and financial reviews have been completed.

"Failure to close a loan application does not indicate that a project doesn't have merit or a strong business case to succeed, but rather that all of the extensive due diligence and legal documentation simply cannot be completed by September 30," LaVera said.

Even as some solar projects appeared in jeopardy, the Energy Department on Friday announced three more loan guarantees for renewable energy projects: $168.9 million for a wind farm in New Hampshire; $350 million for geothermal power in Nevada; and $105 million for a commercial-scale cellulosic ethanol plant in Iowa.

Energy Secretary Steven Chu said the projects will further develop the nation's clean energy resources, create skilled jobs for American workers and help the United States compete with other countries on renewable energy.

Rep. Cory Gardner, R-Colo., said it was important for the committee's investigation of Solyndra to continue.

"The American people deserve answers. Half a billion dollars is missing," he said.

GOP lawmakers said they were expanding their inquiry into the Solyndra loan, which has become a rallying point for Republican critics of the administration's push for so-called green jobs.

Lawmakers said they want the administration to turn over all communications between the Energy Department and White House related to Solyndra, as well as all communications between Energy and the Treasury, which lent Solyndra the money.

Committee leaders said the administration may have violated the law when it restructured Solyndra's loan in February in such a way that private investors moved ahead of taxpayers for repayment in case of default. The economic stimulus law provides for taxpayers to be ahead of other creditors in the event of bankruptcy or default.

Deputy Energy Secretary Daniel Poneman said Thursday that the restructuring was "entirely legal," noting that another aspect of the law requires officials to protect the overall interests of taxpayers. He said the restructuring accomplished that because it gave the struggling company a better chance to succeed.Solyndra filed for Chapter 11 bankruptcy protection earlier this month and laid off its 1,100 employees.

The Fremont, Calif.-based company was the first renewable-energy company to receive a loan guarantee under a stimulus-law program to encourage green energy and was frequently touted by the Obama administration as a model. President Barack Obama visited the company's Silicon Valley headquarters last year, and Vice President Joe Biden spoke by satellite at its groundbreaking ceremony.

Since then, the company's implosion and revelations that the administration hurried Office of Management and Budget officials to finish their review of the loan in time for the September 2009 groundbreaking has become an embarrassment for Obama as he tries to sell his new job-creation program.